Photographic-printing apparatus.



v T. T. SABROE. i PHOTOGRAPHIG PRINTING APPARATUS. APPLICATION PILE'DAPB-.16, 1907.

I91 5 ,044,- I Patented Mar. 9, 1909.

- ATTORNEYS.

UNITED STATES PATENT OFFICE.

THOMAS THOMASSEN SABROE, OF COPENHAGEN, DENMARK.

PHOTOGRAPHIC-PRINTING APPARATUS.

Application filed April 16, 1907.

T 0 all whom it may concern:

Be it known that I, THOMAS THOMASSEN SABROE, of No. 12 Oolbjornsensgade,Copenhagen, in the Kingdom of Denmark, have invented new and usefulImprovements in Photographic-Printing Apparatus, of which the followingis a specification.

In photographic-printing apparatus with the printing cylinder inclosingone or more mercurial vapor lamps which are lighted by a tiltingmovement, such movement has hitherto usually been effected inside thesurface of the cylinder. Usually only the lamp or the lamps were tiltedthe cylinder remaining a fixture. This necessitates a movablearrangement or suspension of the lamps and involves a frequent handlingof these. They are thus liable to being frequently broken. Furthermorethe printingcylinder for the lengths in common use (about 1 meter) mustbe made of a certain considerable diameter, say at least about 15 cm.when a single centrally placed lamp is used and about 20 to 25 cm. whentwo or more lamps are used, in order to allow sufficient room forraising and lowering the ends of the lamp-tube or -tubes. Thereby anunnecessary limit is established for how near to the source of light itis possible to place the printing material. The cylinder being large, itmust in order to be of sufficient strength also be made with thickwalls, whereby the absorption of the more refrangible light isincreased.

In the present invention the risk of breakage is avoided and thepossibility of a better utilization of the light is created by arranginthe entire apparatus to be tilted. Besides this principal arrangementthe inven tion also refers to certain other arrangements resultingtherefrom, particularly the use of narrow printing-cylinders and theguiding of the stretching-cloth or apron under these.

The invention is shown in the accompanying drawing, in which Figures 1and 2 show a photographic printing apparatus for continuous printing inendan side-view respectively, some details having been omitted.

The continuous apparatus shown in Figs. 1 and 2 consists as usual ofsupports a and I) having a recess for the printing-cylinder c andbearings for the top-roller d and the guiding-rollers e and f of theapron. The su ports which are mutually stiiiened by b0 ts g or the likeare not as hitherto pro- Specification of Letters Patent.

Patented March 9, 1909.

Serial No. 368,534.

vided with foot-pieces for being firmly attached to the bed, but are onthe contrary connected to a pair of rockers it. By rocking the apparatusonce up and down on these, for instance in such a way that the righthandend, Fig. 2, is first i'orced downward toward the bed, and then raisedto the same elevation above the normal position shown and finallybrought to rest in this, the lamp will be lighted and the apparatus isnow ready for use. When next, as usual, one of the rollers e, forinstance the leit-hand one in Fig. 1, is turned in a direction oppositeto that of the hands of a clock by a suitable motor, not shown, theprinting cylinder will revolve in the direction of the clock and theprinting material which has been placed on the table 7' with its edgeinserted between the top-roller d and the right-hand roller 6 will thenbe automatically carried around the cylinder 0, pressed in between thelatter and the apron is, Fig. 1, and exposed to the light of the lamp Lso that it comes out finished at the lefthand roller e.

The rocking motion of the apparatus which makes the lighting of the lams possible without their being directly hand ed, may be obtained byother means than those shown in Figs. 1 and 2.

The movable arrangement in question may be applied to apparatus of thetypes already known with loose lamps and wide printingcylinder. It is,however, one of the advantages of this invention that even for lengthsof 1 meter or more the printing-cylinder may be made narrow for instance5 to 9 cm. when using a single central lamp or about 12 cm. when usingtwo or more lamps, and may be made of correspondingly thinner material,for instance to 2 mm. The printing material may thus be broughtcomparatively very near to the lamps so as to be exposed to a stronglyconcentrated light, which has sufiered but slight weakening throughabsorption. In continuously acting apparatus it is further possible tosubstitute one single roller, see the roller f Figs. 1 and 2, for thetwo hitherto used lower guiding-rollers of the apron. This roller may besuspended so as to be movable axially and to act to tighten on the apronby its own weight, and it may be made of wood. In continuously actingapparatus of that kind in which the printing-cylinder, as assumed inFig. 1, is suspended in the apron itself, the use of the narrow cylinderof thin material presents the further advantage that the apron has tocarry only a slight Weight and may thus be made out of less stiffmaterials than it has hitherto been possible to use, for instanceindia-rubber. As has been proved by experi ments, this secures aparticularly eXact contact of the printing-paper against the tracing.

Having noW particularly described and ascertained the natureol' thisinvention and in What manner the same has to be performed, I declarethat What I claim is:

Photographic printing apparatus comprising a frame, a source 'of vacuumarelight carried by the same and adapted to be started by tilting, acopying cylinder surrounding the source of light, rails Which supportthe frame in the middle so that the tilting motion is permitted, andmeans for supporting the frame in the position rel quired by the lightsource. I In testimony, that I claim the foregoing as my invention, Ihave signed my name in l presence of tWo subscribing Witnesses.

THOMAS THOMASSEN SABROE. W'itnesses P. HOFMA BABY, 'EMIL MONRITZEN.

